Thin glass film may be manufactured by one of several techniques. The most common methods are with a fusion draw tower, where molten glass flows over two surfaces, joins over a line, and is drawn into a sheet, or with a re-draw process where a glass plate is heated and drawn into a sheet. Such processes can produce glass film that is less than 100 microns thick and that is flexible enough to be wound into a roll.
Glass film rolls can be used in the same processes as plastic film rolls. For example, a common process applied to plastic film is vacuum coating, which may include physical vapor deposition (including chemical vapor deposition, sputtering, and evaporative coating). While these coating methods are commonly used, they are also expensive. There are several coating methods where conventional roll processing is not generally economically feasible. These include chemical vapor deposition (CVD), low pressure CVD, and atomic layer deposition (ALD), which are all processes commonly used in sheet-based processes where entire plates may be coated at one time. When conventional roll to roll processes can be used, such as batch vacuum roll coating, the process can be very expensive or result in poor coating performance.
There is a need in the art for roll processing of films that provides high performance coatings at a low cost.